The present invention relates to a safety stoppage apparatus for mechanically moved tools, particularly automatic welding guns.
Such apparatuses, which can be used for the most varied purposes, are known in numerous different forms. Apparatuses for the safety stoppage of mechanically moved tools are known in connection with the provision of welding guns on automatic welding machines, e.g. on so-called robot arms. These apparatuses must be constructed in such a way that the swashplate, which preferably carries the tool, namely the welding gun and the assembly plate, which is fixed to the corresponding machine tool, is movable to all sides in an unimpeded manner and solely under the tension of springs. Further, this movement showed ensure a safe and reliable operation of the switch and consequently to an interruption of the work of the corresponding machine tool. In order to avoid damage or destruction, the switch must operate rapidly and easily, it being necessary to continue the swashplate movement following the switching process in the sense of a slowing down or lag.
During this movement between the swashplate and the assembly casing, there must be no rotary movement, i.e. the two parts must be prevented from rotating.